# include<stdio.h>
# include<stdlib.h>

struct ElemType{
    int value;
};

typedef struct TreeNode{
    ElemType data;
    struct TreeNode *lchild, *rchild;
}TreeNode, *BiTree;

// Define a Null tree.
BiTree *root = NULL;

// Insert root Node.
root = (BiTree) malloc (sizeof(BiTree));
root->data = {1};
root->lichild = NULL;
root->rchild = NULL;
